1. Field of the Invention
The present invention is generally related to surgical devices and methods, and in particular, provides a morcellator having a rotating cutting member for severing and removing tissues.
Minimally invasive surgical procedures have gained wide acceptance in the areas of general and gynecological surgery. Minimally invasive techniques are now being developed for therapies of the heart, lung, kidney, and the like. Generally, these procedures make use of one or more small incisions (or other openings) to access internal tissues, often through a cannula, trocar, or other access device. Gas insufflation or fluid distension may be used to enhance the available space within the internal surgical site, and the therapy is often directed with reference to an image provided by an endoscope, a microscope, or using a remote imaging modality such as fluoroscopy, ultrasound, or the like. Generally, minimally invasive surgical procedures minimize patient trauma and speed recovery over traditional open surgical procedures.
Unfortunately, many surgical techniques are difficult to accomplish through laparoscopic cannulas or other minimally invasive access devices. It is sometimes desirable to remove relatively large masses of tissue, for example, to remove a kidney, a partial lung resection, or the like. Removing such large tissue masses laparoscopically through a small access lumen is fairly difficult and time consuming.
Specialized devices have recently been proposed to sever large tissue masses into segments, which are more easily removed. These devices generally include a rotating tube having a sharpened distal end which extends through a fixed outer tube. This sharpened end is inserted into the patient through a cannula, or directly through an incision. The surgeon inserts a grasping device (such as endoscopic forceps or a laparoscopic grasper) through the rotating tube. Grasping the large mass of tissue to be removed, the surgeon pulls the tissue up into the tube, so that the rotating edge severs the grasped portion from the large mass. The size of the severed tissue is generally limited by the outline of the rotating edge, so that the surgeon can continue to pull the severed tissue out of the patient through the rotating tube. By repeating the grasping and severing procedure, surgeons can remove relatively large masses of tissue quite quickly. As the large tissue mass is removed in small, individually grasped morcels, these devices are often referred to as "morcellators".
Although rotating tube morcellators represent a significant advancement in minimally invasive surgical procedures for removing large tissue masses, these known devices still have several significant drawbacks. First, these known devices are relatively large, heavy, and expensive. Sterilizing these devices is fairly time consuming, and sliding motion between the tubes and dulling of the cutting edge limits their useful life. More importantly, work in connection with the present invention has found that friction between the rotating tube and the severed tissue morcel often causes the tissue to turn or twist the grasping instrument in the surgeon's hand. This can significantly lessen the surgeon's ability to control his or her instruments, and can potentially be dangerous for both the patient and the surgeon.
In light of the above, it would be desirable to provide improved methods and devices for removing tissues from internal surgical sites. It would be particularly desirable if these improved methods and devices were adaptable for use with known laparoscopic and other minimally invasive surgical techniques. It would further be desirable if such improved methods and devices enhanced the surgeon's control over the tissue removal procedure, thereby avoiding injury to both the patient and the attending physician, but at a lower cost than known morcellator techniques.
2. Description of the Background Art
An endoscopic morcellator is described in U.S. Pat. No. 5,562,694. A mechanical morcellator is described in U.S. Pat. No. 5,520,634. U.S. Pat. No. 5,439,474 describes a morcellator system, while a related device is described in U.S. Pat. No. 5,443,472. A method and system for removal of tissue from within a body cavity are described in U.S. Pat. No. 5,336,237. A laparoscopic organ retrieval apparatus and procedure is described in U.S. Pat. No. 5,215,521. U.S. Pat. No. 5,176,695 is also relevant.